src/common/colourcmn.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/common/colourcmn.cpp
   3 // Purpose:     wxColourBase implementation
   4 // Author:      Francesco Montorsi
   5 // Modified by:
   6 // Created:     20/4/2006
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Francesco Montorsi
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12
  13 // For compilers that support precompilation, includes "wx.h".
  14 #include "wx/wxprec.h"
  15
  16 #ifdef __BORLANDC__
  17     #pragma hdrstop
  18 #endif
  19
  20 #include "wx/colour.h"
  21
  22 #ifndef WX_PRECOMP
  23     #include "wx/log.h"
  24     #include "wx/utils.h"
  25     #include "wx/gdicmn.h"
  26     #include "wx/wxcrtvararg.h"
  27 #endif
  28
  29 #if wxUSE_VARIANT
  30 IMPLEMENT_VARIANT_OBJECT_EXPORTED(wxColour,WXDLLEXPORT)
  31 #endif
  32
  33
  34 // ----------------------------------------------------------------------------
  35 // XTI
  36 // ----------------------------------------------------------------------------
  37
  38 #if wxUSE_EXTENDED_RTTI
  39
  40 #include <string.h>
  41
  42 template<> void wxStringReadValue(const wxString &s, wxColour &data )
  43 {
  44     if ( !data.Set(s) )
  45     {
  46         wxLogError(_("String To Colour : Incorrect colour specification : %s"),
  47                    s.c_str() );
  48         data = wxNullColour;
  49     }
  50 }
  51
  52 template<> void wxStringWriteValue(wxString &s, const wxColour &data )
  53 {
  54     s = data.GetAsString(wxC2S_HTML_SYNTAX);
  55 }
  56
  57 wxTO_STRING_IMP( wxColour )
  58 wxFROM_STRING_IMP( wxColour )
  59
  60 wxIMPLEMENT_DYNAMIC_CLASS_WITH_COPY_AND_STREAMERS_XTI( wxColour, wxObject,  \
  61                                                       "wx/colour.h",  &wxTO_STRING( wxColour ), &wxFROM_STRING( wxColour ))
  62 //WX_IMPLEMENT_ANY_VALUE_TYPE(wxAnyValueTypeImpl<wxColour>)
  63 wxBEGIN_PROPERTIES_TABLE(wxColour)
  64 wxREADONLY_PROPERTY( Red, unsigned char, Red, wxEMPTY_PARAMETER_VALUE, \
  65                     0 /*flags*/, wxT("Helpstring"), wxT("group"))
  66 wxREADONLY_PROPERTY( Green, unsigned char, Green, wxEMPTY_PARAMETER_VALUE, \
  67                     0 /*flags*/, wxT("Helpstring"), wxT("group"))
  68 wxREADONLY_PROPERTY( Blue, unsigned char, Blue, wxEMPTY_PARAMETER_VALUE, \
  69                     0 /*flags*/, wxT("Helpstring"), wxT("group"))
  70 wxEND_PROPERTIES_TABLE()
  71
  72 wxDIRECT_CONSTRUCTOR_3( wxColour, unsigned char, Red, \
  73                        unsigned char, Green, unsigned char, Blue )
  74
  75 wxEMPTY_HANDLERS_TABLE(wxColour)
  76 #else
  77
  78 #if wxCOLOUR_IS_GDIOBJECT
  79 wxIMPLEMENT_DYNAMIC_CLASS(wxColour, wxGDIObject)
  80 #else
  81 wxIMPLEMENT_DYNAMIC_CLASS(wxColour, wxObject)
  82 #endif
  83
  84 #endif
  85
  86 // ============================================================================
  87 // wxString <-> wxColour conversions
  88 // ============================================================================
  89
  90 bool wxColourBase::FromString(const wxString& str)
  91 {
  92     if ( str.empty() )
  93         return false;       // invalid or empty string
  94
  95     if ( wxStrnicmp(str, wxT("RGB"), 3) == 0 )
  96     {
  97         // CSS-like RGB specification
  98         // according to http://www.w3.org/TR/css3-color/#colorunits
  99         // values outside 0-255 range are allowed but should be clipped
 100         int red, green, blue,
 101             alpha = wxALPHA_OPAQUE;
 102         if ( str.length() > 3 && (str[3] == wxT('a') || str[3] == wxT('A')) )
 103         {
 104             // We can't use sscanf() for the alpha value as sscanf() uses the
 105             // current locale while the floating point numbers in CSS always
 106             // use point as decimal separator, regardless of locale. So parse
 107             // the tail of the string manually by putting it in a buffer and
 108             // using wxString::ToCDouble() below. Notice that we can't use "%s"
 109             // for this as it stops at white space and we need "%c" to avoid
 110             // this and really get all the rest of the string into the buffer.
 111
 112             const unsigned len = str.length(); // always big enough
 113             wxCharBuffer alphaBuf(len);
 114             char * const alphaPtr = alphaBuf.data();
 115
 116             for ( unsigned n = 0; n < len; n++ )
 117                 alphaPtr[n] = '\0';
 118
 119             // Construct the format string which ensures that the last argument
 120             // receives all the rest of the string.
 121             wxString formatStr;
 122             formatStr << wxS("( %d , %d , %d , %") << len << 'c';
 123
 124             // Notice that we use sscanf() here because if the string is not
 125             // ASCII it can't represent a valid RGB colour specification anyhow
 126             // and like this we can be sure that %c corresponds to "char *"
 127             // while with wxSscanf() it depends on the type of the string
 128             // passed as first argument: if it is a wide string, then %c
 129             // expects "wchar_t *" matching parameter under MSW for example.
 130             if ( sscanf(str.c_str() + 4,
 131                         formatStr.mb_str(),
 132                         &red, &green, &blue, alphaPtr) != 4 )
 133                 return false;
 134
 135             // Notice that we must explicitly specify the length to get rid of
 136             // trailing NULs.
 137             wxString alphaStr(alphaPtr, wxStrlen(alphaPtr));
 138             if ( alphaStr.empty() || alphaStr.Last() != ')' )
 139                 return false;
 140
 141             alphaStr.RemoveLast();
 142             alphaStr.Trim();
 143
 144             double a;
 145             if ( !alphaStr.ToCDouble(&a) )
 146                 return false;
 147
 148             alpha = wxRound(a * 255);
 149         }
 150         else // no 'a' following "rgb"
 151         {
 152             if ( wxSscanf(str.wx_str() + 3, wxT("( %d , %d , %d )"),
 153                                                 &red, &green, &blue) != 3 )
 154                 return false;
 155         }
 156
 157         Set((unsigned char)wxClip(red, 0, 255),
 158             (unsigned char)wxClip(green, 0, 255),
 159             (unsigned char)wxClip(blue, 0, 255),
 160             (unsigned char)wxClip(alpha, 0, 255));
 161     }
 162     else if ( str[0] == wxT('#') && wxStrlen(str) == 7 )
 163     {
 164         // hexadecimal prefixed with # (HTML syntax)
 165         unsigned long tmp;
 166         if (wxSscanf(str.wx_str() + 1, wxT("%lx"), &tmp) != 1)
 167             return false;
 168
 169         Set((unsigned char)(tmp >> 16),
 170             (unsigned char)(tmp >> 8),
 171             (unsigned char)tmp);
 172     }
 173     else if (wxTheColourDatabase) // a colour name ?
 174     {
 175         // we can't do
 176         // *this = wxTheColourDatabase->Find(str)
 177         // because this place can be called from constructor
 178         // and 'this' could not be available yet
 179         wxColour clr = wxTheColourDatabase->Find(str);
 180         if (clr.Ok())
 181             Set((unsigned char)clr.Red(),
 182                 (unsigned char)clr.Green(),
 183                 (unsigned char)clr.Blue());
 184     }
 185
 186     if (Ok())
 187         return true;
 188
 189     wxLogDebug(wxT("wxColour::Set - couldn't set to colour string '%s'"), str);
 190     return false;
 191 }
 192
 193 wxString wxColourBase::GetAsString(long flags) const
 194 {
 195     wxString colName;
 196
 197     const bool isOpaque = Alpha() == wxALPHA_OPAQUE;
 198
 199     // we can't use the name format if the colour is not opaque as the alpha
 200     // information would be lost
 201     if ( (flags & wxC2S_NAME) && isOpaque )
 202     {
 203         colName = wxTheColourDatabase->FindName(
 204                     static_cast<const wxColour &>(*this)).MakeLower();
 205     }
 206
 207     if ( colName.empty() )
 208     {
 209         const int red = Red(),
 210                   blue = Blue(),
 211                   green = Green();
 212
 213         if ( flags & wxC2S_CSS_SYNTAX )
 214         {
 215             // no name for this colour; return it in CSS syntax
 216             if ( isOpaque )
 217             {
 218                 colName.Printf(wxT("rgb(%d, %d, %d)"), red, green, blue);
 219             }
 220             else // use rgba() form
 221             {
 222                 colName.Printf(wxT("rgba(%d, %d, %d, %s)"),
 223                                red, green, blue,
 224                                wxString::FromCDouble(Alpha() / 255., 3));
 225             }
 226         }
 227         else if ( flags & wxC2S_HTML_SYNTAX )
 228         {
 229             wxASSERT_MSG( isOpaque, "alpha is lost in HTML syntax" );
 230
 231             // no name for this colour; return it in HTML syntax
 232             colName.Printf(wxT("#%02X%02X%02X"), red, green, blue);
 233         }
 234     }
 235
 236     // this function should alway returns a non-empty string
 237     wxASSERT_MSG(!colName.empty(),
 238                  wxT("Invalid wxColour -> wxString conversion flags"));
 239
 240     return colName;
 241 }
 242
 243 // static
 244 void wxColourBase::MakeMono(unsigned char* r, unsigned char* g, unsigned char* b,
 245                             bool on)
 246 {
 247     *r = *g = *b = on ? 255 : 0;
 248 }
 249
 250 // static
 251 void wxColourBase::MakeGrey(unsigned char* r, unsigned char* g, unsigned char* b
 252                             /*, unsigned char brightness */
 253                            )
 254 {
 255     *r = *g = *b = (wxByte)(((*b)*117UL + (*g)*601UL + (*r)*306UL) >> 10);
 256 }
 257
 258 // static
 259 void wxColourBase::MakeGrey(unsigned char* r, unsigned char* g, unsigned char* b,
 260                             double weight_r, double weight_g, double weight_b)
 261 {
 262     double luma = (*r) * weight_r + (*g) * weight_g + (*b) * weight_b;
 263     *r = *g = *b = (wxByte)wxRound(luma);
 264 }
 265
 266 // static
 267 void wxColourBase::MakeDisabled(unsigned char* r, unsigned char* g, unsigned char* b,
 268                                 unsigned char brightness)
 269 {
 270     //MakeGrey(r, g, b, brightness); // grey no-blend version
 271     *r = AlphaBlend(*r, brightness, 0.4);
 272     *g = AlphaBlend(*g, brightness, 0.4);
 273     *b = AlphaBlend(*b, brightness, 0.4);
 274 }
 275
 276 // AlphaBlend is used by ChangeLightness and MakeDisabled
 277
 278 // static
 279 unsigned char wxColourBase::AlphaBlend(unsigned char fg, unsigned char bg,
 280                                        double alpha)
 281 {
 282     double result = bg + (alpha * (fg - bg));
 283     result = wxMax(result,   0.0);
 284     result = wxMin(result, 255.0);
 285     return (unsigned char)result;
 286 }
 287
 288 // ChangeLightness() is a utility function that simply darkens
 289 // or lightens a color, based on the specified percentage
 290 // ialpha of 0 would be completely black, 100 completely white
 291 // an ialpha of 100 returns the same colour
 292
 293 // static
 294 void wxColourBase::ChangeLightness(unsigned char* r, unsigned char* g, unsigned char* b,
 295                                    int ialpha)
 296 {
 297     if (ialpha == 100) return;
 298
 299     // ialpha is 0..200 where 0 is completely black
 300     // and 200 is completely white and 100 is the same
 301     // convert that to normal alpha 0.0 - 1.0
 302     ialpha = wxMax(ialpha,   0);
 303     ialpha = wxMin(ialpha, 200);
 304     double alpha = ((double)(ialpha - 100.0))/100.0;
 305
 306     unsigned char bg;
 307     if (ialpha > 100)
 308     {
 309         // blend with white
 310         bg = 255;
 311         alpha = 1.0 - alpha;  // 0 = transparent fg; 1 = opaque fg
 312     }
 313     else
 314     {
 315         // blend with black
 316         bg = 0;
 317         alpha = 1.0 + alpha;  // 0 = transparent fg; 1 = opaque fg
 318     }
 319
 320     *r = AlphaBlend(*r, bg, alpha);
 321     *g = AlphaBlend(*g, bg, alpha);
 322     *b = AlphaBlend(*b, bg, alpha);
 323 }
 324
 325 wxColour wxColourBase::ChangeLightness(int ialpha) const
 326 {
 327     wxByte r = Red();
 328     wxByte g = Green();
 329     wxByte b = Blue();
 330     ChangeLightness(&r, &g, &b, ialpha);
 331     return wxColour(r,g,b);
 332 }
 333
 334 #if WXWIN_COMPATIBILITY_2_6
 335
 336 // static
 337 wxColour wxColourBase::CreateByName(const wxString& name)
 338 {
 339     return wxColour(name);
 340 }
 341
 342 void wxColourBase::InitFromName(const wxString& col)
 343 {
 344     Set(col);
 345 }
 346
 347 #endif // WXWIN_COMPATIBILITY_2_6
 348
 349 // wxColour <-> wxString utilities, used by wxConfig
 350 wxString wxToString(const wxColourBase& col)
 351 {
 352     return col.IsOk() ? col.GetAsString(wxC2S_CSS_SYNTAX)
 353                       : wxString();
 354 }
 355
 356 bool wxFromString(const wxString& str, wxColourBase *col)
 357 {
 358     wxCHECK_MSG( col, false, wxT("NULL output parameter") );
 359
 360     if ( str.empty() )
 361     {
 362         *col = wxNullColour;
 363         return true;
 364     }
 365
 366     return col->Set(str);
 367 }
 368
 369